Over 100 seated and standing full-body workouts for specific muscle groupsRequires 1 AAA batteryCompatible with Android and iOS devices

These durable, versatile dumbbells are made from ASTM A48 Class 20 grey iron joined together by a solid 1018 cold rolled steel chrome handle. Noise-reducing rubber is perfect for home use and safe for all flooring. The hex shape prevents rolling and provides stability for floor exercises. The unique ergo handle provides surface area for a firm grip. Available in sizes from 5 to 50 pounds in 5 pounds increments, this set is perfect for targeted muscle works or a full body workout.